The amount of time / energy and even money you have to put into something in order to get certified varies tremendously.
At times, you just finish a 6h online course with a multiple choice exam at the end (most Udemy courses for instance), while others need you to invest a significant portion of spare-time and weekends for half a year in order to build a software-project that will be carefully graded by a jury (Sun Enterprise Architect as an example).
Sometimes you have to spend a four-digit amount on a fairly useless presence course in a fancy Hotel, that gets you nothing but a certificate (Scrum master), while some other free online courses are very worth their time (most Coursera Courses, for instance).
To be clear: earning a certificate does not make someone an expert, sometimes not even a beginner on a topic, experience does.
From my perspective, the one thing that can safely be learned from the certificates a person earned is, what topics he/she is interested in, enough to invest a significant amount of time and learn in a structured way.